1/*-
2 * Copyright (c) 2013 Ian Lepore <ian@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28/* Routines for mapping device memory. */
29
30#include "opt_ddb.h"
31
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/devmap.h>
35#include <vm/vm.h>
36#include <vm/vm_extern.h>
37#include <vm/pmap.h>
38#include <machine/vmparam.h>
39
40static const struct devmap_entry *devmap_table;
41static boolean_t devmap_bootstrap_done = false;
42
43/*
44 * The allocated-kva (akva) devmap table and metadata.  Platforms can call
45 * devmap_add_entry() to add static device mappings to this table using
46 * automatically allocated virtual addresses carved out of the top of kva space.
47 * Allocation begins immediately below the max kernel virtual address.
48 */
49#define	AKVA_DEVMAP_MAX_ENTRIES	32
50static struct devmap_entry	akva_devmap_entries[AKVA_DEVMAP_MAX_ENTRIES];
51static u_int			akva_devmap_idx;
52static vm_offset_t		akva_devmap_vaddr = DEVMAP_MAX_VADDR;
53
54#if defined(__aarch64__) || defined(__riscv)
55extern int early_boot;
56#endif
57
58/*
59 * Print the contents of the static mapping table using the provided printf-like
60 * output function (which will be either printf or db_printf).
61 */
62static void
63devmap_dump_table(int (*prfunc)(const char *, ...))
64{
65	const struct devmap_entry *pd;
66
67	if (devmap_table == NULL || devmap_table[0].pd_size == 0) {
68		prfunc("No static device mappings.\n");
69		return;
70	}
71
72	prfunc("Static device mappings:\n");
73	for (pd = devmap_table; pd->pd_size != 0; ++pd) {
74		prfunc("  0x%08jx - 0x%08jx mapped at VA 0x%08jx\n",
75		    (uintmax_t)pd->pd_pa,
76		    (uintmax_t)(pd->pd_pa + pd->pd_size - 1),
77		    (uintmax_t)pd->pd_va);
78	}
79}
80
81/*
82 * Print the contents of the static mapping table.  Used for bootverbose.
83 */
84void
85devmap_print_table(void)
86{
87	devmap_dump_table(printf);
88}
89
90/*
91 * Return the "last" kva address used by the registered devmap table.  It's
92 * actually the lowest address used by the static mappings, i.e., the address of
93 * the first unusable byte of KVA.
94 */
95vm_offset_t
96devmap_lastaddr(void)
97{
98	const struct devmap_entry *pd;
99	vm_offset_t lowaddr;
100
101	if (akva_devmap_idx > 0)
102		return (akva_devmap_vaddr);
103
104	lowaddr = DEVMAP_MAX_VADDR;
105	for (pd = devmap_table; pd != NULL && pd->pd_size != 0; ++pd) {
106		if (lowaddr > pd->pd_va)
107			lowaddr = pd->pd_va;
108	}
109
110	return (lowaddr);
111}
112
113/*
114 * Add an entry to the internal "akva" static devmap table using the given
115 * physical address and size and a virtual address allocated from the top of
116 * kva.  This automatically registers the akva table on the first call, so all a
117 * platform has to do is call this routine to install as many mappings as it
118 * needs and when the platform-specific init function calls devmap_bootstrap()
119 * it will pick up all the entries in the akva table automatically.
120 */
121void
122devmap_add_entry(vm_paddr_t pa, vm_size_t sz)
123{
124	struct devmap_entry *m;
125
126	if (devmap_bootstrap_done)
127		panic("devmap_add_entry() after devmap_bootstrap()");
128
129	if (akva_devmap_idx == (AKVA_DEVMAP_MAX_ENTRIES - 1))
130		panic("AKVA_DEVMAP_MAX_ENTRIES is too small");
131
132	if (akva_devmap_idx == 0)
133		devmap_register_table(akva_devmap_entries);
134
135	 /* Allocate virtual address space from the top of kva downwards. */
136#ifdef __arm__
137	/*
138	 * If the range being mapped is aligned and sized to 1MB boundaries then
139	 * also align the virtual address to the next-lower 1MB boundary so that
140	 * we end with a nice efficient section mapping.
141	 */
142	if ((pa & 0x000fffff) == 0 && (sz & 0x000fffff) == 0) {
143		akva_devmap_vaddr = trunc_1mpage(akva_devmap_vaddr - sz);
144	} else
145#endif
146	{
147		akva_devmap_vaddr = trunc_page(akva_devmap_vaddr - sz);
148	}
149	m = &akva_devmap_entries[akva_devmap_idx++];
150	m->pd_va    = akva_devmap_vaddr;
151	m->pd_pa    = pa;
152	m->pd_size  = sz;
153}
154
155/*
156 * Register the given table as the one to use in devmap_bootstrap().
157 */
158void
159devmap_register_table(const struct devmap_entry *table)
160{
161
162	devmap_table = table;
163}
164
165/*
166 * Map all of the static regions in the devmap table, and remember the devmap
167 * table so the mapdev, ptov, and vtop functions can do lookups later.
168 *
169 * If a non-NULL table pointer is given it is used unconditionally, otherwise
170 * the previously-registered table is used.  This smooths transition from legacy
171 * code that fills in a local table then calls this function passing that table,
172 * and newer code that uses devmap_register_table() in platform-specific
173 * code, then lets the common platform-specific init function call this function
174 * with a NULL pointer.
175 */
176void
177devmap_bootstrap(vm_offset_t l1pt, const struct devmap_entry *table)
178{
179	const struct devmap_entry *pd;
180
181	devmap_bootstrap_done = true;
182
183	/*
184	 * If given a table pointer, use it.  Otherwise, if a table was
185	 * previously registered, use it.  Otherwise, no work to do.
186	 */
187	if (table != NULL)
188		devmap_table = table;
189	else if (devmap_table == NULL)
190		return;
191
192	for (pd = devmap_table; pd->pd_size != 0; ++pd) {
193#if defined(__arm__)
194		pmap_preboot_map_attr(pd->pd_pa, pd->pd_va, pd->pd_size,
195		    VM_PROT_READ | VM_PROT_WRITE, VM_MEMATTR_DEVICE);
196#elif defined(__aarch64__) || defined(__riscv)
197		pmap_kenter_device(pd->pd_va, pd->pd_size, pd->pd_pa);
198#endif
199	}
200}
201
202/*
203 * Look up the given physical address in the static mapping data and return the
204 * corresponding virtual address, or NULL if not found.
205 */
206void *
207devmap_ptov(vm_paddr_t pa, vm_size_t size)
208{
209	const struct devmap_entry *pd;
210
211	if (devmap_table == NULL)
212		return (NULL);
213
214	for (pd = devmap_table; pd->pd_size != 0; ++pd) {
215		if (pa >= pd->pd_pa && pa + size <= pd->pd_pa + pd->pd_size)
216			return ((void *)(pd->pd_va + (pa - pd->pd_pa)));
217	}
218
219	return (NULL);
220}
221
222/*
223 * Look up the given virtual address in the static mapping data and return the
224 * corresponding physical address, or DEVMAP_PADDR_NOTFOUND if not found.
225 */
226vm_paddr_t
227devmap_vtop(void * vpva, vm_size_t size)
228{
229	const struct devmap_entry *pd;
230	vm_offset_t va;
231
232	if (devmap_table == NULL)
233		return (DEVMAP_PADDR_NOTFOUND);
234
235	va = (vm_offset_t)vpva;
236	for (pd = devmap_table; pd->pd_size != 0; ++pd) {
237		if (va >= pd->pd_va && va + size <= pd->pd_va + pd->pd_size)
238			return ((vm_paddr_t)(pd->pd_pa + (va - pd->pd_va)));
239	}
240
241	return (DEVMAP_PADDR_NOTFOUND);
242}
243
244/*
245 * Map a set of physical memory pages into the kernel virtual address space.
246 * Return a pointer to where it is mapped.
247 *
248 * This uses a pre-established static mapping if one exists for the requested
249 * range, otherwise it allocates kva space and maps the physical pages into it.
250 *
251 * This routine is intended to be used for mapping device memory, NOT real
252 * memory; the mapping type is inherently VM_MEMATTR_DEVICE in
253 * pmap_kenter_device().
254 */
255void *
256pmap_mapdev(vm_paddr_t pa, vm_size_t size)
257{
258	vm_offset_t va, offset;
259	void * rva;
260
261	/* First look in the static mapping table. */
262	if ((rva = devmap_ptov(pa, size)) != NULL)
263		return (rva);
264
265	offset = pa & PAGE_MASK;
266	pa = trunc_page(pa);
267	size = round_page(size + offset);
268
269#if defined(__aarch64__) || defined(__riscv)
270	if (early_boot) {
271		akva_devmap_vaddr = trunc_page(akva_devmap_vaddr - size);
272		va = akva_devmap_vaddr;
273		KASSERT(va >= VM_MAX_KERNEL_ADDRESS - PMAP_MAPDEV_EARLY_SIZE,
274		    ("Too many early devmap mappings"));
275	} else
276#endif
277#ifdef __aarch64__
278	if (size >= L2_SIZE && (pa & L2_OFFSET) == 0)
279		va = kva_alloc_aligned(size, L2_SIZE);
280	else if (size >= L3C_SIZE && (pa & L3C_OFFSET) == 0)
281		va = kva_alloc_aligned(size, L3C_SIZE);
282	else
283#endif
284		va = kva_alloc(size);
285	if (!va)
286		panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
287
288	pmap_kenter_device(va, size, pa);
289
290	return ((void *)(va + offset));
291}
292
293#if defined(__aarch64__) || defined(__riscv)
294void *
295pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, vm_memattr_t ma)
296{
297	vm_offset_t va, offset;
298	void * rva;
299
300	/* First look in the static mapping table. */
301	if ((rva = devmap_ptov(pa, size)) != NULL)
302		return (rva);
303
304	offset = pa & PAGE_MASK;
305	pa = trunc_page(pa);
306	size = round_page(size + offset);
307
308	if (early_boot) {
309		akva_devmap_vaddr = trunc_page(akva_devmap_vaddr - size);
310		va = akva_devmap_vaddr;
311		KASSERT(va >= (VM_MAX_KERNEL_ADDRESS - (PMAP_MAPDEV_EARLY_SIZE)),
312		    ("Too many early devmap mappings 2"));
313	} else
314#ifdef __aarch64__
315	if (size >= L2_SIZE && (pa & L2_OFFSET) == 0)
316		va = kva_alloc_aligned(size, L2_SIZE);
317	else if (size >= L3C_SIZE && (pa & L3C_OFFSET) == 0)
318		va = kva_alloc_aligned(size, L3C_SIZE);
319	else
320#endif
321		va = kva_alloc(size);
322	if (!va)
323		panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
324
325	pmap_kenter(va, size, pa, ma);
326
327	return ((void *)(va + offset));
328}
329#endif
330
331/*
332 * Unmap device memory and free the kva space.
333 */
334void
335pmap_unmapdev(void *p, vm_size_t size)
336{
337	vm_offset_t offset, va;
338
339	/* Nothing to do if we find the mapping in the static table. */
340	if (devmap_vtop(p, size) != DEVMAP_PADDR_NOTFOUND)
341		return;
342
343	va = (vm_offset_t)p;
344	offset = va & PAGE_MASK;
345	va = trunc_page(va);
346	size = round_page(size + offset);
347
348	pmap_kremove_device(va, size);
349	kva_free(va, size);
350}
351
352#ifdef DDB
353#include <ddb/ddb.h>
354
355DB_SHOW_COMMAND_FLAGS(devmap, db_show_devmap, DB_CMD_MEMSAFE)
356{
357	devmap_dump_table(db_printf);
358}
359
360#endif /* DDB */
361